I don't think the author knows what the meaning of "obsolete" is. It's a list of "10 things I didn't know where still being used."
There are several things on that list that are still used because there is still a need for them that no other technology can fulfill. Dot matrix printers, for example. Still used for several different applications, including multipart printing for businesses, and printing those mailers you get where you have to rip the sides off to open.
Interesting that he listed audio tape, but totally ignored vinyl LPs, which are still quite popular among a certain audiophile set.
In particular, though, he seems to completely ignore the fact that a lot of people just aren't comfortable with certain pieces of technology. Fax machines are straightforward devices that almost anyone can manage to make work. How do you replace that in an economical fashion with something that a technophobe can use? Multifunction printer/scanners are either notoriously unreliable or stupidly expensive. (Or both, if you're unlucky.) I've had to fix so many for the various people I know that I can't stand the damn things anymore. I can only imagine handing some of the people I know a signed document and a smartphone, telling them to send someone a copy of that document. They'd freak out, and the recipient would probably end up with 12 blurry pictures of a desktop, and a few accidental selfies. Not to mention that smartphones cost several hundred dollars, and have to be replaced every couple of years.
Meh... overall, the article was ignorant and elitist.
